Synthesis and vibrational spectra of some 2-alkoxy-5,6-benzo-1,3,2-dioxastibepines

Abstract

1) Tranesterification of the respective antimony trialkoxides with phthalyl alcohol have 2-methoxy-, 2-ethoxy-, and 2-tert-butoxy-5,6-benzo-1,3,2-dioxastibepines. 2) According to the IR and Raman spectra, 2-ethoxy- and 2-tert-butoxy-5,6-benzo-1,3,2-dioxastibepines are polymerized in the crystalline phase; the νSb-O frequencies are at least 100 cm-1 higher in melt and in solution than in the crystalline phase; they exist both as dimer and monomer. 2-tert-butoxy-5,6-benzo-1,3,2-dioxastibepine exists predominantly in the chair conformation. © 1987 Plenum Publishing Corporation.